U.S. Pat. No. 3,616,000 discloses a low-friction bearing sleeve having a cylindrical resin body reinforced by glass filaments embedded therein. Such a bearing is capable of supporting relatively high radial loads when properly supported and fixed in the bore of a rigid supporting housing. A somewhat similar bearing having a square or noncircular bore and a cylindrical outer glass filament reinforced resin body has similar capabilities.
A telescoping drive-line such as for agricultural implements generally has a square inner shaft and a tubular outer shaft which includes a sleeve at one end with a square bore in which the inner shaft is axially slideable. Such a drive-line requires dependable lubrication because of the high pressure loads due to the high torque loads which are imposed sometimes while there is no relative axial motion. Fitting a square liner in the square bore to provide a low-friction sliding bearing surface which does not require lubrication has been proposed. However, ordinary injection molded plastics with a low-friction inner face have not been considered adequate in strength because of the distortion which is due to the clearances which are more or less unavoidable. This will be further explained hereinafter.
U.S. Pat. No. 3,700,295 describes and claims a resin-bodied outer race or socket for a ball and socket bearing and having overlying glass filament reinforcing which includes filaments extending from each end face of the socket to its cylindrical outer face. However, the layers of glass filaments here are not concentrated at one location or another as is provided by the present invention.